People have needed to move and perform feats of strength and endurance for for most of history, so we evolved to feel better when we’re able to do that.
Furthermore, an exercise regimen introduces a positive habit, keeping up with which helps you feel more accomplished.
However, if a person with mental health problems also has neurological or physical problems that are exacerbated by exertion, a full-on exercise regime isn’t likely to help — although frequent walks and low-intensity workouts like stretching could have some benefit.
I have schizotypal personality disorder and chronic fatigue, so while I’m not able to go the whole nine yards, taking a walk a couple times a week noticeably improves my mood and energy levels. You do what you can.
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